What kind of riddle is this? The second line literally says that the south is a mountainchain. At least the other lines tried to (very shallowly) hide the ocean and forest. The amaryllis line is pretty well obscuring though. I didnt know what it was (recognized name faintly, but not something I remember) so I had to google, and all I get is a red flower. I doubt flowers refer to plains, so dunno what kind of biome its meant to be, maybe volcano?. As for the area itself, sounds like it is describing a crater from a meteorite impact.